Pseudisobrachium is one of the biggest genera with 190 species from the world including one extinct species from France. In Korea, only one species, P. koreana Lim, has been recorded. The ecological information of Pseudisobrachium is poorly studied, however, it was recorded that Pseudisobrachium species are found associated with various ants in several previous studies. As results of taxonomy studies on the Korean bethylids, a new species of Pseudisobrachium is discovered based on one female specimen which was collected from Cheongsong county (Gyeongbuk province) by Malaise trap in 2008. This is the first record of female of the genus in Korea. A taxonomic discussion on the genus Pseudisobrachium, diagnosis and diagnostic characteristics of the new species are provided.

Bethylus Latreille, a type genus of the family Bethylidae, is represented by about 32 species and is recorded fromthe Palaearctic and the Nearctic regions. In East Asia, the genus has been reported from Far Eastern Russia, China andJapan. The genus was well-known as ectoparasitoid of micro-lepidopteran insects including gelechiids, coleophorids.As results of taxonomic study on Korean Bethylinae, the distribution of Bethylus is newly confirmed in South Koreaand the species was identified as B. fuscicornis (Jurine, 1807). We provide the description, diagnostic illustrations of B.fuscicornis and a key to Korean genus of Bethylinae.

Members of Bethylidae are widely distributed from the Tropic to the Subarctic regions around the world. The family contains about 2,216 species worldwide, and the majority of recorded species are found from the tropical regions. From the Oriental region, 368 species of 46 genera in four subfamilies has been recorded up to date. Two species are recognized as new to science and three to the fauna of Cambodia and its adjacent countries in the present study. We provide microphotographs and diagnoses of each species with a general introduction of Cambodian bethylids.

A bethylid genus, Pararhabdepyris Gorbatovskii (Hymenoptera: Bethylidae: Epyrinae) which consists of three species worldwide, is reported for the first time in Korea. Pararhabdepyris paradoxus Gorbatovskii is redescribed with detail illustrations of morphological diagnostic characteristics. A key to the genus of Epyrinae in Korea is also provided.

Bethylidae is the largest family of Chrysidoidea (Hymenoptera: Aculeata) and distributed widely from the tropics to the subarctic regions around the world. Most members of the family are relatively small, and are generally known as ectoparasitoids of immature stages of Lepidoptera and Coleoptera. Some species have been used and studied as natural enemies of various insect pests in some countries. Even though the family Bethylidae is important group as natural enemies in the agricultural and forestry fields, fundamental researches on this group such as a faunal study have not carried out and poorly known in Korea. Since 2005, we have carried out the faunal investigation of Korean Bethylidae and more than 1,600 specimens were collected by 2010, with some of their host insects. As results of present study, fifty two species belongs to sixteen genera of Bethylidae are recognized in Korea, including seven previously recorded species as of 2006. We will introduce on the biodiversity of Korean Bethylidae and its applied aspects as potential biocontrol agents against various insect pests with cases of their usages.

Prorops Waterston is a small genus of the family Bethylidae (Hymenoptera) with just four species known worldwide: P. nasuta Waterston (cosmopolitan), P. petila Evans (Nearctic, Neotropical); P. obsoleta Evans (Neotropical); P. rakan Terayama (Palaearctic). A new species is recognized from the tropic rain forest of Cambodia. It is characterized from congeneric species by ‘the elongated median process on the lower part of frons and the flat-broad mandible downwardly developed’. The new species is described and illustrated with a key to world species of the genus Prorops.

Goniozus Förster which is belonging to the subfamily Bethylinae (Hymenoptera: Bethylidae), are one of the large genera, and consist of approximately 170 species worldwide. Most members of Goniozus are ectoparasitoids of immature stages of microlepidopteran families, mainly Gelechiidae, Pyralidae and Tortricidae. As a results of this study, a total of five species of the genus Goniozus are recognized in Korea, which includes two new species, two newly recorded species and a previously recorded species. Diagnosis and illustrations for each species are presented.

Three species, Allobethylus tomoae Terayama, Cephalonomia tarsalis (Ashmead), and Laelius yamatonis Terayama of the subfamily Epyrinae are recorded for the first time in Korea. Both sexes of A. tomoae Terayama, C. tarsalis (Ashmead) and female of L. yamatonis Terayama are briefly described with diagnostic morphological illustrations for each species based on the Korean specimens. Male of the genus Allobethylus is discovered for the first time from the word.

Six species of the Pristocerinae are recognized from Korea, including two new species (Pseudisobrachium sp. nov., Parascleroderma sp. nov.), and four species new to Korea (Acrepyris minutus (Yasumatsu 1955), Apenesia elegans Terayama 1999, A. okinawensis Terayama 1999, and Pristocera formosana Miwa et Sonan 1935). The illustrations of diagnostic characters are presented with a key to species of Korean Pristocerinae is provided.

Sclerodermus harmandi populations were collected from 6 Korean regions (Seoul, Gangwon, Chungcheong, Jeolla, Gyeonasang and Jeju provinces), 1 Chinese region (Nanjing) and 1 Japanese region (Tokyo). Above all was identified as the same species based on morphological characteristics. In present study, we compared the intra-specific characteristics of regional isolated populations of S. harmandi based on nucleotide and amino acid sequences of variant genomic and mitochondrial loci: the full length of internal transcribed spacer 1 and 2 (ITS1 & ITS2), the complete cytochrome oxidase subunit I and II (COI & COII) and tRNA genes for aspartate and lysine and 5'end of ATPase 8 genes. There were no significant differences among the analysed 9 populations regardless of regional segregation. The nucleotide and translated amino acid sequences similarities were significantly high, despite some sequence differences were found in same loci. This result support the report based on the morphological characteristics. However, we are conducting further study to identify whether sequence differences in specific loci are the characteristics of individual level in population or population level and to analyse the full sequences of mitochondrial DNA by regional segregation.

Odontepyris sp. nov., a new ectoparasitoid on the caterpillar of Telorta divergens (Butler, 1879) (Lepidoptera: Noctuidae), is recognized from Korea. After rearing the larvae on the host insect, adult females were obtained and described. Revising all known species of genus Odontepyris, a key to the species of the genus Odontepyris is presented for the Eastern Palearctic region.

This study was performed to investigate the immature development period, fecundity, emergence rate and sex ratio of Sclerodermus harmandi against different host insects, Monochamus alternatus, M. saltuarius and Psacothea hilaris. Full grown larvae and pupae of host insects were provided with foods. The mean larval period of S. harmandi female was 29.2±0.93 and 25.1±0.47 days in larvae and pupae of M. alternatus, 27.1±0.41 and 26.0±0.69 days in M. saltuarius, and 26.3±0.38 and 31.2±0.24 days in P. hilaris, respectively. S. hilaris adults were emerged at 12.9±0.2 days in female and 11.9±0.2 days in male after pupation when hosted M. alternatus pupa. Development period in male showed shorter one day than in female. Success rate of oviposition against different hosts was higher as 98.6 and 97.5% on full grown larva and pupa of M. saltuarius. Emergence rate was higher as 90.1 and 87.3% on M. saltuarius larvae and pupae. Sex ratio of emerged S. harmandi adults was approximately 10:1 (Female : Male), females showed higher emergence rate than males. The period until first oviposition after emergence in S. harmandi female was the shortest in 4.6±0.1 days on M. saltuarius pupa. When three females of S. harmandi were inoculated on M. saltuarius larva, the number of laid eggs was the highest 62.7±2.5 per female.

South Korean species of the bethylid wasps, genus Holepyris are reviewed. Ten species are recognized and eight of them are described as new to science: H. crinitus sp. nov., H. dimidium sp. nov., H. discedo sp. nov., H. mucro sp. nov., H. multo sp. nov., H. profundus sp. nov., H. secedo sp. nov., H. tantillus sp. nov.; Holepyris benten Terayama 2006 and H. susanowo Terayama 1999 are recorded for the first time from South Korea. Diagnostic characteristics and illustrations of each species are provided.